May weather forecast
Napa Junction, CA

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Weather in May

May, the last month of the spring in Napa Junction, is an agreeable month, with an average temperature fluctuating between 72°F (22.2°C) and 49.6°F (9.8°C).

Temperature

With the onset of May, Napa Junction's average high-temperature clocks in at an agreeable 72°F (22.2°C), showing a minor fluctuation from the previous month. From the heights of the May heat, Napa Junction records a mean nighttime low of 49.6°F (9.8°C).

Humidity

The average relative humidity in May in Napa Junction is 66%.

Rainfall

In Napa Junction, in May, it is raining for 4.7 days, with typically 0.63" (16mm) of accumulated precipitation. In Napa Junction, during the entire year, the rain falls for 68.2 days and collects up to 11.93" (303mm) of precipitation.

Daylight

In Napa Junction, the average length of the day in May is 14h and 16min.
On the first day of May in Napa Junction, sunrise is at 6:11 am and sunset at 8:00 pm. On the last day of the month, sunrise is at 5:47 am and sunset at 8:26 pm PDT.

Sunshine

The average sunshine in May in Napa Junction, California, is 10.9h.

UV index

The average daily maximum UV index in May is 5. A UV Index estimate of 3 to 5 represents a moderate threat to health from unprotected exposure to Sun's UV rays for ordinary individuals.
Note: A maximum UV index of 5 in May translates into the following recommendations:
Take precautions - Protection against skin and eye damage is obliged. UV radiation is strongest from the Sun during midday; protect yourself by staying in shaded areas. A hat with a broad brim is indispensable, filtering out up to half of UV rays.
Updated: Feb 10, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate

Frequently asked questions

What are May temperatures in Napa Junction?

In Napa Junction, 72°F (22.2°C) is the average high-temperature and 49.6°F (9.8°C) is the average low-temperature during May.

What is the average humidity in May in Napa Junction?

The average relative humidity in May is 66%.

How many days does it rain in May in Napa Junction?

In May, the rain falls for 4.7 days. Throughout May, 0.63" (16mm) of precipitation is accumulated.

What is the average length of the day in May in Napa Junction?

In May, the average day length in Napa Junction is 14h and 16min.

When are sunrise and sunset in May in Napa Junction?

On the first day of May in Napa Junction, California, sunrise is at 6:11 am and sunset at 8:00 pm. On the last day of the month, sunrise is at 5:47 am and sunset at 8:26 pm PDT.

How long on average sun shines in May in Napa Junction?

In Napa Junction, California, the average sunshine duration in May is 10.9h.

How high is the UV index in May in Napa Junction?

The average daily maximum UV index in May in Napa Junction is 5. A UV Index estimate of 3 to 5 represents a moderate vulnerability from exposure to the Sun's UV radiation.
Average humidity
Average rainfall days
Average daylight
Average sunshine
Average sunshine days
Average UV index
Average cloud cover
Average visibility

Average temperature in May
Napa Junction, CA

Average temperature in May - Napa Junction, CA
  • Average high temperature in May: 72°F

The warmest month (with the highest average high temperature) is July (82.6°F).
The month with the lowest average high temperature is December (54.9°F).

  • Average low temperature in May: 49.6°F

The month with the highest average low temperature is August (56.5°F).
The coldest months (with the lowest average low temperature) are January and December (42.3°F).

Average pressure in May
Napa Junction, CA

Average pressure in May - Napa Junction, CA
  • Average pressure in May: 29.97"Hg

The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.91"Hg).

Average wind speed in May
Napa Junction, CA

Average wind speed in May - Napa Junction, CA
  • Average wind speed in May: 6.6mph

The windiest month (with the highest average wind speed) is May (6.6mph).
The calmest month (with the lowest average wind speed) is November (4.5mph).

Average humidity in May
Napa Junction, CA

Average humidity in May - Napa Junction, CA
  • Average humidity in May: 66%

The month with the highest relative humidity is March (75%).
The month with the lowest relative humidity is September (58%).

Average rainfall in May
Napa Junction, CA

Average rainfall in May - Napa Junction, CA
  • Average rainfall in May: 0.63"

The wettest month (with the highest rainfall) is February (2.32").
The driest months (with the least rainfall) are July and August (0.04").

Average rainfall days in May
Napa Junction, CA

Average rainfall days in May - Napa Junction, CA
  • Average rainfall days in May: 4.7 days

The month with the highest number of rainy days is March (11.9 days).
The month with the least rainy days is August (0.9 days).

Average daylight in May /
Average sunshine in May
Napa Junction, CA

Average daylight in May / Average sunshine in May - Napa Junction, CA
  • Average daylight in May: 14h and 2min

The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 36min).

  • Average sunshine in May: 10h and 5min

The months with the most sunshine are July and August (Average sunshine: 12h and 0min).
The month with the least sunshine is December (Average sunshine: 5h and 42min).

Average sunshine days in May
Napa Junction, CA

Average sunshine days in May - Napa Junction, CA
  • Average sunshine days in May: 25.7 days

The months with the most sunshine days are July and August (29.1 days).
The month with the least sunshine days is March (18.3 days).

Average UV index in May
Napa Junction, CA

Average UV index in May - Napa Junction, CA
  • Average UV index in May: 5

The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 3).

Average cloud cover in May
Napa Junction, CA

Average cloud cover in May - Napa Junction, CA
  • Average cloud cover in May: 23

The month with the most cloud cover is March (Cloud cover 37).
The month with the least cloud cover is July (Cloud cover 7).

Average visibility in May
Napa Junction, CA

Average visibility in May - Napa Junction, CA
  • Average visibility in May: 6mi

The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).

Napa Junction, California, USA

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